We present high-resolution VLA observations of the molecular gas in the host galaxy of the highest-redshift quasar currently known, SDSS J1148+5251 (z = 6.42). Our VLA data of the CO(3−2) emission have a maximum resolution of 0.17 × 0.13 arcsec2 (≤ 1 kpc2), and enable us to resolve the molecular gas emission both spatially and in velocity. The molecular gas in J1148+5251 is extended to a radius of 2.5 kpc, and the central region shows 2 peaks, separated by 0.3 arcsec (1.7 kpc). Assuming that the molecular gas is gravitationally bound, we estimate a dynamical mass of ∼ 4.5 × 1010M☉ within a radius of 2.5 kpc. This dynamical mass estimate leaves little room for matter other than the detected molecular gas, and — in particular — the data are inconsistent with a ∼ 1012 M☉ stellar bulge, which would be predicted based on the M BH —σ bulge relation.